Office of Research and Development National Exposure Research Laboratory Photo image area measures 2” H x 6.93” W and can be masked by a collage strip of one, two or three images. The photo image area is located 3.19” from left and 3.81” from top of page. Each image used in collage should be reduced or cropped to a maximum of 2” high, stroked with a 1.5 pt white frame and positioned edge-to-edge with accompanying images. Scale and Complexity in Environmental Systems Daniel A. Vallero, Ph.D. National Exposure Research Laboratory U.S. Environmental Protection Agency

Office of Research and Development National Exposure Research Laboratory 1 Environmental Protection: A Child of the ’60s Systematic mandates from NEPA: EIS CEQ

Office of Research and Development National Exposure Research Laboratory 2 Scale is crucial

Office of Research and Development National Exposure Research Laboratory 3 Regulatory Focus Varies Policy –National consistency –Command and control Technology (Clean Air Act in the 1990s) Risk –Assessment (science) –Management (policy) –Communication (everything) –Residual risk (Clean Air Act now) –Safe products (TSCA/FIFRA) –Health based standards (Clean Water and Safe Drinking Water Acts) –Manifests (RCRA, Right to Know) –Response (Superfund, Contingency Plan, Spill Response…)

Office of Research and Development National Exposure Research Laboratory 4 Mission of Engineers (Adapted from: Department of Materials Science and Engineering, State University of New York at Stony Brook) The engineer must envision and allow for the creation of something, following certain specifications, which performs a given function. What we design must perform its function without fail.

Office of Research and Development National Exposure Research Laboratory 5 But eventually, everything fails… So, designers must strive to avoid failure, in all of its forms. In particular, we must avoid catastrophic failures: –loss of designed property or properties potentially affected by the application of the design; –damage to the environment where the design is applied, and; –Most importantly injury and loss of life. Modern designers can learn what to do and NOT to do to create designs with less of a chance of failure.

Office of Research and Development National Exposure Research Laboratory 6 Example of Range of Acceptability –Design of a barrier under a waste facility may reduce the flow of water carrying hazardous materials to m s –1

Office of Research and Development National Exposure Research Laboratory 7 Design Success Water Table Contaminants

Office of Research and Development National Exposure Research Laboratory 8 Example of Range of Acceptability –Design of a barrier under a waste facility may reduce the flow of water carrying hazardous materials to m s –1 –But, it does not eliminate the flow entirely –The designer must keep the flow rate low

Office of Research and Development National Exposure Research Laboratory 9 Design Success Water Table Contaminants

Office of Research and Development National Exposure Research Laboratory 10 Example of Range of Acceptability –Design of a barrier under a waste facility may reduce the flow of water carrying hazardous materials to m s –1 –But, it does not eliminate the flow entirely –The designer must keep the flow rate low –Catastrophic failure at Q = m s –1 !

Office of Research and Development National Exposure Research Laboratory 11 Perception is crucial Which line is longer? The Müller-Lyer Illusion.

Office of Research and Development National Exposure Research Laboratory 12 Perception is crucial Which line is longer? The Müller-Lyer Illusion.

Office of Research and Development National Exposure Research Laboratory 13 Perception is crucial Which line is longer? The Müller-Lyer Illusion.

Office of Research and Development National Exposure Research Laboratory 14 Perception is crucial Which line is longer? The Müller-Lyer Illusion.

Office of Research and Development National Exposure Research Laboratory 15 Perception is crucial Which line is longer? The Müller-Lyer Illusion.

Office of Research and Development National Exposure Research Laboratory 16 Perception is crucial Which line is longer? The Müller-Lyer Illusion.

Office of Research and Development National Exposure Research Laboratory 17 But sometimes, perception is pretty accurate…. Source: Pardon, ca

Office of Research and Development National Exposure Research Laboratory 18 Risk Perception Failures become "disasters" as a function of public perception of risk. –For example, in 1992, same number of U.S. fatalities in transportation accidents involving airplanes (775), trains (755), and bicycles (722). –Public perception of the risk from air travel is often much higher than that for trains and bicycles. Two apparent reasons: –large loss of life and associated media attention from an air crash, and –air passenger's lack of control over their environment in the case of air or, to a lesser degree, rail accidents. But there are many reasons behind these perceptions

Office of Research and Development National Exposure Research Laboratory 19 Risk Communication Report Data True Meaning (Signal) Data Reduction Interpretation (Information) S/N = ∞ Report ? Noise S/N = Low

Office of Research and Development National Exposure Research Laboratory 20 Different Processes at Work* Analytical PhaseRisk Assessment ProcessesRisk Perception Processes Identifying risk Physical, chemical, and biological monitoring and measuring of the event Personal awareness Deductive reasoningIntuition Statistical inference Estimating risk Magnitude, frequency and duration calculations Personal experience Cost estimation and damage assessment Intangible losses and non- monetized valuation Economic costs Evaluating risk Cost/benefit analysisPersonality factors Community policy analysisIndividual action *Adapted from K. Smith, 1992

Office of Research and Development National Exposure Research Laboratory 21 Risk is quantifiable... Risk = f(Hazard x Exposure) A probability, a fraction Part of our everyday lives –Different for each of us –Basis for decision-making

Office of Research and Development National Exposure Research Laboratory 22 Risk Assessment Defined: Risk assessment is a process where information is analyzed to determine if an environmental hazard might cause harm to exposed persons and ecosystems. Paraphrased from the “Risk Assessment in the Federal Government” (National Research Council, 1983)

Office of Research and Development National Exposure Research Laboratory 23 A Paradigm for Risk

Office of Research and Development National Exposure Research Laboratory 24 A few words about toxicity and uncertainty in scale Cancer versus non-cancer Cancer uses slope factor Non-cancer uses reference dose (RfD) or reference concentration (RfC) RfC is for air, RfD for other exposure pathways No safe level of exposure to a carcinogen (no threshold, no NOAEL)

Office of Research and Development National Exposure Research Laboratory 25 Dose-Response: A Way to Define a Hazard A B B C Adverse Effect Dose NOAEL

Office of Research and Development National Exposure Research Laboratory 26 Dose-Response: No threshold for cancer Cancer Non-cancer Adverse Effect Dose NOAEL

Office of Research and Development National Exposure Research Laboratory 27 Dose-Response: Safety in Reference Dose Adverse Effect Dose NOAEL RfD = NOAEL MF  UF

Office of Research and Development National Exposure Research Laboratory 28 Dose-Response: Safety in Reference Dose Adverse Effect Dose NOAEL RfD RfD = NOAEL MF  UF

Office of Research and Development National Exposure Research Laboratory 29 Improved Certainty Includes Better Scale and Complexity Factors Adverse Effect Dose NOAEL RfD RfD = NOAEL MF  UF

Office of Research and Development National Exposure Research Laboratory 30 Calculating Exposures: Amount of Hazard Reaching Us Where, E =personal exposure during time period from t 1 to t 2 C(t) =concentration at interface, at t.

Office of Research and Development National Exposure Research Laboratory 31 Exposure bridges the physical and social sciences Where, E =personal exposure during time period from t 1 to t 2 C(t) =concentration at interface, at t. Chemistry & Physics Psychology & Sociology

Office of Research and Development National Exposure Research Laboratory 32 Components of Exposure Science Measurements (Orange Boxes) Models (Green Lines)

Deposition to aquatic ecosystem M 0, M 2+ M-C x H y Linking Human and Exposure Analysis for a Single Contaminant (Mangis et al.) Speciation Environmental Measurements & Modeling

Deposition to aquatic ecosystem M 0, M 2+ M-C x H y Food Chain Uptake Linking Human and Exposure Analysis for a Single Contaminant Speciation Environmental Measurements & Modeling Ecosystem function & structure Activity and Function Measurements & Modeling

Deposition to aquatic ecosystem M 0, M 2+ M-C x H y Food Chain Uptake Linking Human and Exposure Analysis for a Single Contaminant Atmospheric emissions Natural: Forest fires, volcanoes Industrial: Power plants Population Diet Uncertainties: Amounts consumed Fish species consumed Fish preparation etc. Ground water transport Natural & industrial sources Temporal Variability Uncertainties: Intra-annual Inter-annual Fish species Fish maturation Fish size etc. Regional Economy Uncertainties: Local vs. imported fish Pricing and availability Processing, storage etc. Speciation Environmental Measurements & Modeling Ecosystem function & structure Activity and Function Measurements & Modeling

Deposition to aquatic ecosystem M 0, M 2+ M-C x H y Food Chain Uptake Linking Human and Exposure Analysis for a Single Contaminant Atmospheric emissions Natural: Forest fires, volcanoes Industrial: Power plants Population Diet Uncertainties: Amounts consumed Fish species consumed Fish preparation etc. Ground water transport Natural & industrial sources Temporal Variability Uncertainties: Intra-annual Inter-annual Fish species Fish maturation Fish size etc. Regional Economy Uncertainties: Local vs. imported fish Pricing and availability Processing, storage etc. Speciation Environmental Measurements & Modeling Ecosystem function & structure Activity and Function Measurements & Modeling Dietary Ingestion

Atmospheric emissions Natural: Forest fires, volcanoes Industrial: Power plants Population Diet Uncertainties: Amounts consumed Fish species consumed Fish preparation etc. Absorption, Distribution Metabolism, Elimination and Toxicity (ADMET) Modeling Uncertainties: Age, gender, lifestyle differences Physiological variability Physicochemical and biochemical variabilities Health status, activities Pregnancy/nursing Genetic susceptibilities Ground water transport Natural & industrial sources Temporal Variability Uncertainties: Intra-annual Inter-annual Fish species Fish maturation Fish size etc. Deposition to aquatic ecosystem M 0, M 2+ M-C x H y Target Tissue Dose Brain Kidney Breast milk Fetus / fetal brain Food Chain Uptake Linking Human and Exposure Analysis for a Single Contaminant Toxicity/Adverse Effect Neurological Renal Cardiovascular [Genomic / Cytomic] Regional Economy Uncertainties: Local vs. imported fish Pricing and availability Processing, storage etc. Dietary Ingestion Speciation Environmental Measurements & Modeling Ecosystem function & structure Activity and Function Measurements & Modeling PBTK and BBDR Modeling Biomarkers & Eco- Indicators

Atmospheric emissions Natural: Forest fires, volcanoes Industrial: Power plants Population Diet Uncertainties: Amounts consumed Fish species consumed Fish preparation etc. Absorption, Distribution Metabolism, Elimination and Toxicity (ADMET) Modeling Uncertainties: Age, gender, lifestyle differences Physiological variability Physicochemical and biochemical variabilities Health status, activities Pregnancy/nursing Genetic susceptibilities Ground water transport Natural & industrial sources Temporal Variability Uncertainties: Intra-annual Inter-annual Fish species Fish maturation Fish size etc. Deposition to aquatic ecosystem M 0, M 2+ M-C x H y Target Tissue Dose Brain Kidney Breast milk Fetus / fetal brain Food Chain Uptake LOOKING BACK: RECONSTRUCTION Toxicity/Adverse Effect Neurological Renal Cardiovascular [Genomic / Cytomic] Regional Economy Uncertainties: Local vs. imported fish Pricing and availability Processing, storage etc. Dietary Ingestion Speciation Environmental Measurements & Modeling Ecosystem function & structure Activity and Function Measurements & Modeling PBTK and BBDR Modeling Biomarkers & Eco- Indicators

Office of Research and Development National Exposure Research Laboratory 39 Advances in the Bayesian Network Applications Usually, limited available data And, limited resources Need reliable information for human and eco decision making Need a predictive link between actions & results (eco & health)

Office of Research and Development National Exposure Research Laboratory 40 Typical Approach Models try to combine understanding from many projects into one predictive framework  Simulating all physical, chemical and biological processes at some state  Highly variable interrelationships among these processes  So, probably better to tailor each relationship’s detail than to choose a scale identical for all processes.

Office of Research and Development National Exposure Research Laboratory 41 Bayesian Networks When data and resources are limited… Graphical structure represents cause-and-effect assumptions between system variables Such assumptions let causal chain from actions to eco and human consequences to be factored into sequence of conditional probabilities

Office of Research and Development National Exposure Research Laboratory 42 Bayes Theorem allows myriad forms of information like this to be combined:

Office of Research and Development National Exposure Research Laboratory 43 Sample (monitoring data) Posterior (integrating modeling and monitoring) Bayesian Analysis: Combining Information Prior (model forecast) Criterion Concentration

Office of Research and Development National Exposure Research Laboratory 44 Log chl a Log P Log(chla)= Log(P) Std. Err. =.120 Prior Sample Posterior Probability Lake Consequences of actions on ecosystem and human exposure can be predicted.

Office of Research and Development National Exposure Research Laboratory 45 These are conditional probability models that: can be mechanistic, statistical, judgmental use probability to express uncertainty use Bayes theorem for adaptive implementation updating. Bayes (Probability) Networks

Nitrogen Inputs River Flow Cause and Effect Relationships Cause and Effect Relationships Algal Density Carbon Production Frequency of Hypoxia Number of Fishkills Fish Health Shellfish Abundance Duration of Stratification Harmful Algal Blooms Sediment Oxygen Demand Chlorophyll Violations

Sediment Oxygen Demand Duration of Stratification River Flow Algal Density Carbon Production Frequency of Hypoxia Number of Fishkills Nitrogen Inputs Fish Health Chlorophyll Violations Harmful Algal Blooms Shellfish Abundance Dependencies are described by conditional probability distributions. p(Hypoxia |SOD, Strat.)

All model relationships can be disaggregated into a series of conditional distributions. Sediment Oxygen Demand Duration of Stratification River Flow Algal Density Carbon Production Frequency of Hypoxia Number of Fishkills Nitrogen Inputs Fish Health Chlorophyll Violations Harmful Algal Blooms Shellfish Abundance p(C|N) = p(C|A) p(A|N,R) p(R) separate Each conditional distribution can be represented by a separate sub-model.

Office of Research and Development National Exposure Research Laboratory 49 Sediment Oxygen Demand Duration of Stratification River Flow Algal Density Carbon Production Frequency of Hypoxia Cross-SystemComparison SimpleMechanistic ExpertElicitation Number of Fishkills Nitrogen Inputs Fish Health Chlorophyll Violations Harmful Algal Blooms Shellfish Abundance Empirical Model Seasonal Regression Site-Specific Application Survival Model

Office of Research and Development National Exposure Research Laboratory 50 p(Health = “Poor” | N inputs = “X”) Sediment Oxygen Demand Duration of Stratification River Flow Algal Density Carbon Production Frequency of Hypoxia Number of Fishkills Nitrogen Inputs Fish Health Chlorophyll Violations Harmful Algal Blooms Shellfish Abundance Once the model is complete, conditional probabilities can easily be computed.

Office of Research and Development National Exposure Research Laboratory 51 Example of how outcomes can be predicted 90% Risk of Exceedance

Office of Research and Development National Exposure Research Laboratory 52 50% Risk of Exceedance 90% Risk of Exceedance Example of how outcomes can be predicted

Office of Research and Development National Exposure Research Laboratory 53 Application: Fecal-origin pathogen exposure

Office of Research and Development National Exposure Research Laboratory 54 New emphases Multimedia, compartmental Interfaces and integrations –Human and Ecosystem –Time and Space

Office of Research and Development National Exposure Research Laboratory 55 Emerging Technologies Always a part of engineering Balance between innovation and carelessness… Ignorance is not an option, nor is ignoring the breakthroughs…. So, we need to manage the risks and take advantage of the opportunities.

Office of Research and Development National Exposure Research Laboratory 56 Nanotechnology – Good or Bad? Answer: Yes… Things are different down there. Carbon is not carbon….

Office of Research and Development National Exposure Research Laboratory 57 Membranes Adsorbents Oxidants Catalysts Sensing Analytical The Good: Nanomaterial-enabled tools for environmental engineers* *Thanks to Mark Wiesner.

Office of Research and Development National Exposure Research Laboratory 58 Conventional ‘permeable reactive barrier’ made with millimeter- sized construction-grade granular Fe Tratnyek and Johnson (2005)

Office of Research and Development National Exposure Research Laboratory 59 ‘Reactive treatment zone’ Formed by sequential injection of nano-sized Fe Makes overlapping zones of particles adsorbed to the grains of native aquifer material

Office of Research and Development National Exposure Research Laboratory 60 Treating much more mobile contaminants Same approach can be used to treat nonaqueous phase liquid (DNAPL) contamination by injection of mobile nanoparticles

Office of Research and Development National Exposure Research Laboratory 61 The Bad: Nanomaterials themselves can change physical and chemical behavior and may be hazardous. Much variability in mobility of nanoparticles even in the same size range (Wiesner again) Change in concentration [1-C/C 0

Office of Research and Development National Exposure Research Laboratory 62 And, toxicity is even more uncertain… Human cell line toxicity (Sayes, Colvin, et al., 2004) toxic but not mobile not toxic, but mobile

Office of Research and Development National Exposure Research Laboratory 63 Group Project: What is a Pollutant? Hypothetical* Case: ZGA and the Forklift Answer 3 Questions: 1.Is air a hazard? 2.Is air a pollutant? 3.Is the company entitled to coverage per the pollution exclusion clause? *Sort of….

Office of Research and Development National Exposure Research Laboratory 64 Near Road Exposures Concentration gradient Micrometeorology Fluid dynamics Traffic dynamics

Office of Research and Development National Exposure Research Laboratory 65 Near Road Exposures: Importance of Variability 5 yrs of hourly data Saw the same thing in at Ground Zero (WTC)

Office of Research and Development National Exposure Research Laboratory 66 Near Road Exposures: What Should Be Measured? Continuous sampling: PM 2.5PM 2.5 COCO NO xNO x Elemental CarbonElemental Carbon 1-hr integrated sampling: BenzeneBenzene 1,3-butadiene1,3-butadiene FormaldehydeFormaldehyde AcetaldehydeAcetaldehyde AcroleinAcrolein PM 2.5 (24-hr)PM 2.5 (24-hr)

Office of Research and Development National Exposure Research Laboratory 67 Environmental Justice Toxic Waste and Race (United Church of Christ study) Found direct correlation between minority population and likelihood of waste site EJ neighborhood defined: –Disproportionate exposure to contaminants –SES and racial makeup

Office of Research and Development National Exposure Research Laboratory 68 Unique challenges of EJ Historically, communities have had little or no “voice” So, the prototypical environmental response models don’t work well –Based upon complaints Must deal with trust issues … and disenfranchisement. So, we need a different paradigm –Intervention –Outreach and how we report what we find.

Office of Research and Development National Exposure Research Laboratory 69 EJ: Culture Is Crucial Left: Brick making kiln in Ciudad Juarez. Right: El Paso-Ciudad Juarez airshed during a thermal inversion. Photo credit: Environmental Defense

Office of Research and Development National Exposure Research Laboratory 70 But sometimes, EJ is less obvious (but more ubiquitous) Vinclozolin, a fungicide, is an endocrine disruptor But two of its degradation products are even more anti- androgenic than the parent vinclozolin How are people exposed?

Office of Research and Development National Exposure Research Laboratory 71 Time integrated dicarboximide flux from sterilized soil with pore water pH7.5, after incorporation of 5mL of 2g L -1 fungicide suspension and a 2.8mm rain event (95% CI).

Office of Research and Development National Exposure Research Laboratory 72 Time integrated dicarboximide flux from non-sterile soil with pore water pH7.5, after incorporation of 5mL of 2g L -1 fungicide suspension and a 2.8mm rain event (95% CI).

Office of Research and Development National Exposure Research Laboratory 73 Worker and family exposures shortly after field re-entry: Greater inhalation exposures to more toxic endocrine disruptors in first few hours. Farm worker and family activities are determinants of risk

Office of Research and Development National Exposure Research Laboratory 74 Greenhouse effect is a physical concept So, what is this truth that is so inconvenient?

Office of Research and Development National Exposure Research Laboratory 75 But, you can have too much of a good thing.

Office of Research and Development National Exposure Research Laboratory 76 What is that we value? Sentinel species?

Office of Research and Development National Exposure Research Laboratory 77 Let’s talk about models….

Office of Research and Development National Exposure Research Laboratory 78 Our way of life…?

Office of Research and Development National Exposure Research Laboratory 79 And who’s to blame…?

Office of Research and Development National Exposure Research Laboratory 80 Inconvenient You Me Or that guy… behind the tree?

Office of Research and Development National Exposure Research Laboratory 81 Let’s talk about science Objectivity Soundness Precision Accuracy Relevance

Office of Research and Development National Exposure Research Laboratory 82 But, when is risk acceptable?

Office of Research and Development National Exposure Research Laboratory 83 Good science also means we need to be open to the possibility that we are wrong.

Office of Research and Development National Exposure Research Laboratory 84 In fact, environmentalism is not science… "...it is now time for us to make a major shift in our thinking about the environment, similar to the shift that occurred around the first Earth Day in 1970, when this awareness was first heightened. But this time around, we need to get environmentalism out of the sphere of religion. We need to stop the mythic fantasies, and we need to stop the doomsday predictions. We need to start doing hard science instead.” --Michael Crichton

Office of Research and Development National Exposure Research Laboratory 85 The Truth Whether it is inconvenient or not, we need to be scientific. Scientist search for truth. We must be open and honest about what we do not know (ala Socrates). We must be open-minded to new paradigms. The one requirement of science is that the truth be told at all times (C.F. Snow).

Office of Research and Development National Exposure Research Laboratory 86 The need for scientists is growing We need new technologies to address these problems…. We need better data to see what is really happening… We need a better informed public, especially about things scientific YOU And most importantly, we need YOU!

Office of Research and Development National Exposure Research Laboratory 87 The Very Bottom Line Need a balance: … between risk assessment and risk management … between risk assessment and risk perception … and between opportunities and risks.

Office of Research and Development National Exposure Research Laboratory Photo image area measures 2” H x 6.93” W and can be masked by a collage strip of one, two or three images. The photo image area is located 3.19” from left and 3.81” from top of page. Each image used in collage should be reduced or cropped to a maximum of 2” high, stroked with a 1.5 pt white frame and positioned edge-to-edge with accompanying images. Contact me: